Head skim?

[martyn92]

Been cleaning up the head and found this on cylinder 4,theres a ring about half the way round the cylinder, its smooth in places and rough in others.



Im guessing it will need skimming?

[Dave]

How have you been cleaning it up, flat surface or sand paper?

[martyn92]

Got all of the old gasket and thick rust off with a blade, then went over it with a flat (had it machined flat) piece of metal with 800 wet and dry lightly. The old headgasket has done that im sure of it

[Ruan]

Yeah thats the ring that seals the combustion chamber... I'll guess that it had one of those wank fibre gaskets with rings on it rather tHan a proper steel gasket...

I'd get that skimmed as thats exactly the place it needs to seal the best...

[martyn92]

I think its the original gasket from 94. Do I need to remove the valves before getting it skimmed?

Also, I haven't cleaned the block up yet but is it likely to be the same ?

[Frosty]

The valves don't need to be removed for skimming.

[martyn92]

Decided to get it skimmed, rather be safe than sorry!

Is it normal after changing to hdi rods that the crank is harder to turn than before?

[darrenjlobb]

Decided to get it skimmed, rather be safe than sorry!

Is it normal after changing to hdi rods that the crank is harder to turn than before?

Nothing should be harder to turn....do you mean harder compression? Or just harder right thro the cycle?

Correct choice to skim that, just asking for trouble if not!

[martyn92]

I reinserted piston 1 and it was much easier to turn after that plus I had only just nipped up the end caps but after I had tightend the end caps fully that made a big differnce too !
However I now have this problem ... http://306oc.co.uk/forum/thread-14421.html